ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Photopolymerization of MMA was carried out at 40°C in bulk and in diluted systems using quinoline-chlorine (Q-Cl2) C.T. complex as the photoinitiator. Bulk polymerization followed normal free radical kinetics (initiator exponent = 0,5) for [Q-Cl2] 〈0,0015 mol.1-1. In diluted systems, variable monomer exponents were observed, ranging from slightly above 1 to 2,7, depending on the nature of the solvent (benzene, carbon tetrachloride, chloroform, chlorobenzene, acetone, dioxane, THF and DMF). Initiator exponent was ≤0,5 in diluted systems and it even became practically equal to zero depending on the nature of solvent and the level of dilution. The kinetic non-ideality in diluted systems was explained on the basis of solvent-retardation and initiator-termination via degradative chain transfer involving solvent-modified initiating complexes and chain radicals. The actual initiating complex appeared to be the (Q-Cl2)-monomer complex formed instantaneously in situ on addition of Q-Cl2 complex to the monomer.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1980.021811216
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